Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

%
%
g

Test String

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r#"<link\s+(?:[^>]*?\s+)?href=(["']).*?(fonts\.googleapis\.com).*?\1*>"#).unwrap(); let string = "<!-- joomla head --> <link href=\"https://musterdomain.at/images/icon.png\" rel=\"shortcut icon\" type=\"image/png\" sizes=\"any\" /><link href=\"https://fonts.googleapis.com/css2?family=Open+Sans:ital,wght@0,300;0,400;0,600;0,700;0,800;1,300;1,400;1,600;1,700;1,800&display=swap\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://fonts.googleapis.com/css2?family=Ubuntu:ital,wght@0,300;0,400;0,500;0,700;1,300;1,400;1,500;1,700&display=swap\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://fonts.googleapis.com/css2?family=Ropa+Sans:ital,wght@0,400;1,400&display=swap\" rel=\"stylesheet\" type=\"text/css\"> <link href=\"https://musterdomain.at/media/system/css/joomla-fontawesome.css?e9f3c2476322ea574b407689a02666d5\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://use.fontawesome.com/releases/v6.2.0/css/all.css\" data-version=\"6.2.0\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://musterdomain.at/media/templates/site/tp_easy/css/compiled-901cb97c530df6ff377f9a49a4c09cd4.css?e9f3c2476322ea574b407689a02666d5\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://musterdomain.at/media/astroid/assets/vendor/astroid/css/debug.css?e9f3c2476322ea574b407689a02666d5\" rel=\"stylesheet\" type=\"text/css\" /> <link href=\"https://musterdomain.at/media/templates/site/tp_easy/css/compiled-dbb71e3836394a80bbece49d2d30c5be.css?e9f3c2476322ea574b407689a02666d5\" rel=\"stylesheet\" type=\"text/css\" /> <!-- head styles -->"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Rust, please visit: https://docs.rs/regex/latest/regex/